Hydraulic system for operating a crimping tool



March 7, 1961 M. 1.. KLINGLER 2,973,625

HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 15, 1957 6 Sheets-Sheet 1 INVENTOR.

MARTIN LKuNel ER.

BY I

March 7, 1961 M. 1.. KLINGLER (2,973,625

HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 15, 1957 6 Sheets-Sheet 2 INVENTOR.

1' MARTIN Lhmcun March 7, 1961 M.. L. KLINGLER HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 13, 1957 6 Sheets-Sheet 3 March 7, 19 1 I M. L. KLINGLER 2,973,625

HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 15, 1957 e Sheets-Sheet 4 I II 46 INVENTOR.

NARTI N LKlINGlER! March 7, 1961 M. L. KLINGLER 2,973,625

HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 13, 1957 6 Sheets-Sheet 5 Elli INVENTOR. MARTIN L l\u N6 [in March 7, 1961 M. L. KLINGLER 7 ,625

HYDRAULIC SYSTEM FOR OPERATING A CRIMPING TOOL Filed Sept. 13, 1957 6 Sheets-Sheet 6 INVENTOR.

llmwm LKLINGIIR BY original condition.

crimping head B and ahandle C. head B is fitted' onto the handle (3, which is con-- nected to the actuating assembly -A" by means of a nrnnxuue SYSTEM'FOR O ER T A CRIMPING TOOL -Martin L. Kliuger,'Hershey, Pa., assignor to AMP Incorporated, Harrisburg-Pa.

rneus t. 13, 1951, Ser.No. 683,874 I 10Claims.. cries-52y This invention relates to an assembly for actuating hydraulic. tools, particularly tools for crimping electrical qq aes rs 9M o d r T equ p n may be t i d in srimp na a s Si e o e s .(eI- 1 0 W re) requiring high "crimping pressure (e.g. 8000 p.s.i.).

The tool'of the instant invention is of the hydraulic type, operated by a switch located in the crimping head. After the crimp is completed, the assembly automatically disables itself, shuts the 'motor' oh? and returns to its i The QQl'remains disabled iuntil a second switch is operated. This acts as a safety feature since thetool cannot be actuated inadvertently butmust be returned to an operative condition before another crimp can'be eiiected. Also the tool can be operated so thatthe. i in h r m n t o ly m v thr part of the stroke, wherebyit may grasp the connector between the dies'and hold the eonnector in position until a conductor is inserted therein. The strokemay then be completed to make the crimped connection.

Other objects and attainments of the present invention will becomeapparentto those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which there is shown and described aniliustrative embodiment of the invention. It is to be understood, however, that this embodiment is not intended to be exhaustive nor :limiting of the invention but is given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify it in various forms, each as may be best suited to the conditions of a particular use.

In the drawings: 7

Figure 1 is ajperspective View of a crimping tool and I actuating assembly embodying principles of this invention;

Figure 2 is a perspective view of the aetua'tin'g assemy; I v

Figure 3 is a top View of the actuating assembly; 0 Figure 4 is a sectional view taken along lines IV1 V of Figure 3;

Figure 4A is a view similar to Figure 4, showing the solenoid in a difierent position;

of Figure 3; v

Figure 6 is an exploded view of the tool handle showing the operating switches;

Figure is a sectional view taken along lines VTV 2,973,625 Patented Mar. 7, 1.961

members 16 and 18 are operably located in the head.

The actuating assembly, Figures 2 and 3, includes ,a 'motorZil, a pump 22, switch box 24, solenoid26, valve assembly 28, limit switch 3%, -fluid reservoir 32 (shown in phantom on Figure 2), as well as the necessary fittings, connections, sealing rings, etc.

The electric motor 2% drives the pump 22 via belt 21 (Figure 8), which pumps fluid from the reservoir 32, through valve 28, to the crimping tool B. When the maximum crimping pressure is obtained, valve 28 causes the motor to be shut oli and vpermits the fluid in the crimping head fluid motor to return to the reservoir (to be described more fully later).

The valve assembly (Figure 7) comprises a block member 34 with a straight through iiuid passage 36, having an inlet port 38 connected to the pump 22, and an outlet port iii connected to the crimping tool fluid motor. A second fluid passage 42 connects the main .passage 36 to a retu'rnpassage 44, leading back to the reservoir. The fluid. passage 42 is normally closed I A by-passvalve 5th is seated ina fluid passageway 52,

which also communicates with the main passageway 36. This valve. may be a spring operate d, one.-way check valve, adjusted to overcome the resistance of the spring 54 when the system attains the maximum desired crimping pressure. Opening of the byepass valve Stipermits fluid to enter passageway 56, and chamber 6%, to drive thepiston 62. The piston rod 64 bears against lever 66 causing it to pivot into the position shown in Figure 5. This has a two-fold effect. One end of the lever trips limit switch 3%, thus shutting off the motor 2% The other end of the leverdepresses plunger 4%, opening ball check valve 46 and permitting fluid in the head fluid motor to return to the reservoir through passageways 42, 44, etc. Y i

Reductionof fluid pressure in the system releases the valve 46 with fluid trapped in chamber- 60, so that the assembly is retained in this final position until the fluid is released ,by operation of solenoid pin I68, secured to a solenoid26. Apredetermined reduction of pressure results in closing of valve 46 and trapping of fluid in 66 because valve 50 also closes. As shown .in Figure 4, the retraction of the solenoid pin permits the fluid to escape from chamber 60 into the chamber 7o,-and then into'fluid'passage 72, passage 74, and (Figure 7 .evene tually into the reservoir return pipe 44.

-Noting Figures 4 and 4-A, the solenoid :pin 63-ihas an outside diameter equal to the inside diameter of the chamber 70. However, the inside diameter of the chamber 71, between the passage 56 and the chamber 60 (Figures 4 and 7), is of a larger diameter than the solenoid pin 68, to permit fluid flow between passage 56, and chamber 60, regardless of the position of the solenoid pin.

In the preferredcmbodiment the reservoir return line i 74 etc. (Figure 4) also communicates (passageway 72 Figure 7 is a view similar to Figue 5, showing the valve assembly ina different position; I

Figure8 is'a bottom view of; the actuatingassembly;

an actuating assembly ,A (with a cover thereon), a The crimping hydraulic hose :10, and an electrical conductor 12. Die I extended) with-the line 36 which supplies fluid to the crimping tool. A valve 78, which is hand operated by means of a screw threaded handle (Figures 2 and-4) normally closes this-passageway.

The crimpingf'handle, Figure .6, iscomprised of. two half sections 82,.which fit together to form apistohgrip, with the fluid line 84 located centr ally therein. A trigger guard 86 surrounds switch actuator '88 which operatescontact switch 91. A second (switch actuator 92 operates control switch 94. V

A standard crimping head, such aslthe type shown in the patent to Stoltz 2,722,859,,rnay be employed.

' Operation *With a connector and conductor -in' crimping position between the dies 16, 18, the switch 91 (Figure 6 and Figure 9) is operated, through actuator 88, to start the motor 20 (Figure 3). The motor 20 drives the pump 22 (Figure 8) -to draw fluid from the reservoir 32, and drive it through the main line 36 (Figure 7) of the valve assembly. The fluid is then conducted to the exit port 40, high pressure line 10 (Figure 1) and the fluid motor in crimping head B, to drive the movable die 16 toward the fixed die 18, to crimp the connector and conductor therebetween.

When the fluid pressure required to effect a satisfactory crimped connection has been attained, the valve 50 (Figure 7) opens. Spring 54 is preset so that the valve 50 will open automatically when the pressure in the system reaches the predetermined amount.

Opening of valve 50 permits fluid flow through passageways 52, 56, 71 and into chamber 60, where the fluid raises the piston 62. The piston rod 64 pivots the lever 66. As previously described this shuts off the motor (switch 30) and opens the fluid return valve 46.

A spring (not shown) in the head B (Figure 1) causes the piston operated die 16 to return to its normal position, thus forcing fluid back through the hose 10, and back through the fluid return line 44 thence to the reservoir 32. When the fluid pressure in the system decreases to a point where it is less than the force generated by the spring 54 (Figure the valve 50 again closes under the action of the spring. However, fluid trapped in the chamber 60 maintains the lever 66 in the position shown in Figure 5, with the motor shut off and fluid return valve open. The system will be held in this condition until it returns to equilibrium and will remain inoperative until reset by the solenoid switch actuator 92. This acts as a safety feature, preventing inadvertent operation of the tool.

When it is desired to reuse the tool, the switch actuator 92 (Figure 6) is depressed to actuate the switch 94 thus operating the solenoid 26. The solenoid retracts the pin 68 from the full line position shown in Figure 4 to the position shown in Figure 4-A, long enough to permit fluid to escape from chamber 60 back to the reservoir. The pin then returns to its original position. Bleeding fluid from the chamber 60 permits the piston 62 to return to its original position. A spring 90 retracts the lever 66, thus energizing motor switch 30 and permitting ball valve 46 to be seated. The assembly is then ready to crimp another connector through actuation of switch 91.

In making a crimped connection it is desirable to locate the connector in the crimping die while leaving one hand free to thread the conductor into the connector. With the tool shown in the drawings, the dies may be brought together until they lightly grip a connector therebetween. The crimping is interrupted by releasing switch actuator 88 and a conductor is inserted into the connector. The crimping cycle is then completed.

If it becomes necessary to retract the crimping die 16 prior to the completion of the crimp, it may be accomplished by releasing hand valve 80 (Figure 4). This permits fluid to bleed out of the head B and high pressure line 10, through passage 72, back to the reservoir. Thus the die may be completely or partially retracted.

After completion of the crimp, during the return stroke of the dies, the die travel may be stopped at any intermediate point by depressing the switch actuator 92, thus operating the solenoid to bleed the fluid from chamber 60, which in turn permits lever 66 to return to its normal position and closes the fluid return valve 46. Since the fluid in the hose can no longer return to the reservoir further retraction of the die 16 is prevented.

Changes in construction will occur to those skilled in the art and various apparently diflerent modifications and embodiments may be made without departing from the scope ofthe invention. The matter set forth in the foregoing description and accompanying drawings is oflered by way. of illustration only. The actual scope of v the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

,I claim:

1. An assembly for actuating a fluid operated crimping tool including: a fluid reservoir, a fluid line between the reservoir and a fluid motor for operating the tool, a pump in said fluid line for conveying fluid under pressure from the reservoir to the fluid motor, a pump motor connected to said pump, a switch means for controlling a pump motor operatively connected to the pump, a fluid passageway communicating with the fluid line and the reservoir, valve means normally closing said fluid passageway and operable at a predetermined pressure to open the fluid passageway to permit fluid to flow from the fluid line into the reservoir, and means responsive to a predetermined fluid pressure in the line for opening the valve means and holding it open until reset as well as simultaneously operating the switch to shut off the pump motor, whereby the tool will be disabled and the fluid permitted to bleed out of the fluid motor back to the reservoir after the crimping pressure has been attained.

2. In a motor driven actuating assembly for conducting fluid from a reservoir to a fluid motor for operating a tool, the improvement comprising: an actuating block, a fluid passageway through the block for conveying fluid from the reservoir to the fluid motor, a pump means connected with the fluid passageway for driving fluid from the reservoir to the fluid motor, a pump motor driving said pump means, a cylinder in the block communicating with the passageway, a piston in said cylinder with a piston rod projecting to the exterior of the block, a valve means between the passageway and the chamber normally closed while fluid is conducted to the fluid motor but opened at a predetermined pressure to pass pressurized fluid to operate the piston, a second passageway in the block for conveying fluid from the fluid motor back to the reservoir, a second valve means in.

the second passageway for preventing fluid from returning from the fluid motor back to the reservoir, and means operated by the piston rod for shutting off the pump motor and opening the second valve means to permit fluid to return to the reservoir.

3. In a motor driven actuating assembly for conducting fluid from a. reservoir to a fluid motor for operating a tool, the improvement comprising: an actuating block, a fluid passageway through the block for conveying fluid from the reservoir to the fluid motor, a pump means connected with the fluid passageway for driving fluid from the reservoir to the fluid motor, a pump motor driving said pump means, a cylinder communicating with the passageway, a piston in said cylinder with a projecting piston rod, a first valve means between the passageway and the chamber which is closed while fluid is being conducted to the fluid motor but operable at a predetermined pressure to pass pressurized fluid to operate the piston, a second passageway in the block for conveying fluid from the fluid motor back to the reservoir, a second valve means in the second passageway for preventing fluid from returning from the fluid motor back to the reservoir, means for shutting otf the pump motor and opening the second valve means to release the fluid in the fluid motor when the predetermined pressure has been reached, said means comprising a pivoted lever operated by the piston rod, a duct between the piston chamber and the second passageway, and a solenoid operated valve blocking said duct, whereby the fluid is trapped in the chamber until the solenoid valve is actuated to an open position.

4. .An assembly for actuating a fluid operated crimping tool including: a block, a main fluid passageway through the block, one end connected to a fluid supply, the other end connected to a fluid motor whereby fluid may flow to the fluid motor, a second fluid passageway connected to the first fluid passageway adapted to permit flow of fluid from the fluid motor back to the reservoir, a pump motor operatively connected to a pump, said pump connected to the first passageway, a valve normally closing said second passageway and means for simultaneously opening the valve and shutting off the pump motor upon the attainment of the desired pressure including: a chamber in the block, a piston in the chamber with the piston rod projecting to the exterior of the block, a branch fluid passageway between the chamber and the first passageway, a valve in said branch passageway, resilient means holding said valve in closed position until the fluid pressure reaches a predetermined valve wherein it opens and permits fluid to flow into the chamber, means operated by the piston rod for simultaneously shutting oif the pump motor and opening the valve in the second passageway, and means for bleeding fluid from the chamber to reset the system for another cycle.

5. A crimping assembly including: a tool, a fluid motor for operating said tool, a fluid supply, a fluid line extending between the fluid supply and the fluid motor, a means for propelling the fluid from the supply to the fluid motor, a return line from the fluid motor to the supply, releasable means closing the return line, means for releasing said means and shutting off the means for propellingthe fluid, said means being automatically actuated when the fluid line reaches a predetermined pressure and being maintained in its actuating position until reset.

6. The tool of claim 5 including a solenoid operated valve for resetting the assembly.

7. A sub-assembly for controlling fluid flow from a fluid supply through a motor-operated system, with a normally closed fluid return line and simultaneously controlling the power supply line to the motor including: a pivoted lever, a piston rod for pivoting said lever, said piston rod secured to a piston seated in a cylinder, said piston operated by the fluid pressure in the system, said lever operable between one position wherein it opens the return line and de-energizes the power supply, and

a second position wherein it permits closure of the return line and activates the power supply, resilient means normally urging said lever into its second position, a normally closed check-valve between the piston and the fluid supply which opens at a preset fluid pressure to permit fluid to operate the piston, a fluid passageway between the cylinder and the return line, and means in said fluid passageway operable between a position where it closes the passageway and a position where it permits fluid flow therethrough.

8. A tool for crimping electrical connectors including a fluid motor for actuating the tool, a pump motor, a pump operated by said pump motor to deliver fluid from a reservoir through a fluid passage in a control assembly to the fluid motor, a second fluid passage between the fluid motor and the reservoir to return the fluid, and control means in the assembly for automatically shutting off the pump motor and simultaneously opening the return fluid passageway when a predetermined pressure has been reached and maintaining this condition until reset.

9. The device recited in claim 8 wherein the control means includes a valve means in the second fluid passage and a piston operated lever operable between a first position wherein it actuates the pump motor and closes the return valve and a second position wherein it disables the pump motor and opens the return valve.

10. The device of claim 9 including: a releasable check-valve means for trapping fluid in the chamber to lock the lever in the second position after the fluid motor has been operated.

References Cited in the file of this patent UNITED STATES PATENTS 2,457,467 Hartman Dec. 28, 1948 2,729,063 Hoadley Jan. 3, 1956 2,756,563 Bohlman et al. July 31, 1956 FOREIGN PATENTS 463,568 Great Britain Apr. 2, 1937 

